Oil burners



Nov. 7, 1961 J. M. FURDOCK 3,007,515

011. BURNERS Filed Nov. 14, 1955 2 Sheets-Sheet 1 Nov. 7, 1961 J. M. FURDOCK on BURNERS 2 Sheets-Sheet 2 Filed Nov. 14, 1955 INVENT OR ATTORNEYS United Stats This invention relates to oil burners and more particularly to an improved form of burner head or combustion head for a device of this chara-cter.

In the case of oil burners for domestic and other purposes, the fuel is usually atomized by being forced through a relatively fine opening in a fuel nozzle and air is delivered to the atomized fuel outside of the spray which issues from the nozzle opening.

In order to obtain a proper combustible mixture of air with the fuel, it is desirable that the air be given a Whirling or turbulent motion so that it will be thoroughly mixed with the fuel. It is also desirable to provide for secondary air in addition to that which i introduced to the fuel spray on the outside of the combustion head. This secondary air may be introduced through the combustion head in contrast to that on the outside thereof so that it will pass directly over the fuel nozzle. According to the structure of the present invention, primary air will be directed around the combustion head, past and through helical vanes upon the head so as to give this air a turbulent or whirling motion. It will then be directed through an annular passage of conical shape, this passage being formed partly by the shape of the forward part of the combustion head and partly by the shape of a cap secured to the casing or housing of the burner, which casing is usually of cylindrical shape. This cap is secured interiorly of the casing and is provided with a conical interior surface which cooperates with the conical exterior surface of the forward part of the combustion head to form the annular cone-shaped or inwardly directed passage referred to.

In addition improved means is provided for directing the secondary air into the combustion head. This air is furnished by the same source as that which furnishes the primary air, and while a part of the secondary air may pass directly through a shutter or other opening at the back of the combustion head, a part of such air is deflected by the vanes on the exterior surface of the combustion head and caused to pass through openings upon the periphery of the head into the hollow interior about the nozzle. The rear ends of the vanes are so shaped as to perform this function of deflecting the air into these openings and the latter are arranged at the bases of the vanes.

It sometimes occurs that when the burner is shut off, the flame is apt to be drawn back into the nozzle due to the fact that a partial vacuum seems to exist within the nozzle. structure, and for this purpose vacuum breaker openings are formed in the forward portion of the combustion head to admit air into the forward portion of the latter adjacent the discharge opening of the nozzle to insure that a partial vacuum is not formed at this point.

One object of the present invention is to provide an oil burner having a burner head of novel construction whereby the combustion air delivered to the burner head will be properly mixed with the spray of oil issuing from the nozzle of the oildelivery tube.

Such an occurrence is prevented by the present atom A further object of the invention is to provide a combustion head of novel construction for an oil burner, the burner head being so formed as to impart a whirling motion or turbulence to the air delivered around the head, the combustion head being so shaped that it cooperates with a portion of the exterior casing to direct this whirling mass of air inwardly toward the spray of oil issuing from the nozzle.

Still another object of the invention is to provide a combustion head of novel construction for an oil burner such that the combustion air will be directed around the combustion head and inwardly toward a point directly in front of the oil delivery nozzle and also directed into the combustion head around and in contact with the delivery nozzle.

To these and other ends the invention consists in the novel features and combinations of parts to be hereinafter described and claimed.

In the accompanying drawings:

FIG. 1 is a sectional view of an oil burner structure embodying my invention;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a top plan plan view of the combustion head removed from the casing;

FIG. 4 is a front elevational View of the combustion head shown in FIG. 3;

FIG. 5 is a sectional View of the combustion head on line 5-5 of FIG. 1;

FIG. 6 is a longitudinal sectional view of an oil burner showing a combustion head of modified form;

FIG. .7 is a top plan view of the combustion head removed from the housing; and

FIG. 8 is a sectional view of the combustion head on line 8-8 of FIG. 7.

To illustrate a preferred embodiment of my invention, I have shown in the drawings an oil burner comprising an outer housing 10 of substantially cylindrical for-m. Within the forward end of the housing 10 is a cap 11 which may be secured to the housing by screws or the like 12. This cap is of cylindrical shape exteriorly but is provided with a tapered interior wall 13 in the form of a frustum of a cone, the wall being of circular shape but tapering inwardly and forwardly so as to direct air passing thereover toward its axis.

The combustion head proper is shown more especially in FIGS. 3, 4 and 5, and consists of a section having a substantially cylindrical portion 14 and a forward tapered or cone-shaped portion 15. As shown more especially in FIG. 1, this section of the head is hollow so that air directed thereinto may pass therethrough.

Upon the cylindrical portion 14 are provided a plurality of helically directed vanes 16 which extend over the length of this portion of the front section of the head and are of sufiicient height or width so that their outer edges stand in close juxtaposition to the inner surface of the housing 10. At their forward ends the outer surfaces or edges of these vanes contact the inner conical wall 13 of the cap 11, as shown at 17 in FIG. 1, to position the head relatively to the cap 11 and the housing 10. The forward conical portion 15 of this section of the combustion head is provided with a number of vacuum breaker openings 18 through the wall thereof so that there will be communication between the interior of the head and the conical space between the wall 13 and the memher so as to permit air directed past the vanes 16 to enter the head adjacent the nozzle. Four of these openings are shown but any desired number may, of course, be provided as is deemed necessary.

Rearwardly of the forward section of the combustion head is a hollow drum member 20 which may be secured to the portion 14 by screws or the like 21. This drum member may be provided with a transverse web 22 extending diametrically across the interior thereof, this web receiving the fuel tube 23 is an opening therethrough, the tube being held in place by the set screw 24. The nozzle 25 is secured on the forward end of the tube 23 within the combustion head, and the tube may be turned laterally and extended outwardly through the wall of the casing 10, as shown at 26.

A shutter mechanism 27 may be provided at the rear of the drum 20, which shutter is provided with openings to permit a flow of air into the interior of the drum 20 and the combustion head from the casing 10. This shutter may be adjustable if desired, so that the effective area of the openings may be varied.

Also the drum 20 is provided with a plurality of openings 28 adjacent its forward end and adjacent the rear edge of the cylindrical portion 14 of the head. It will be noted that each of these openings is in registration with the rear edge of one of the vanes 16. The rear edges of these vanes may be made of tear-drop shape, as shown at 29, so that the vane is slightly thicker at its rear end than over the remaining portion of its length in order to form a baffle for the air passing over the vanes and direct a part of this air through the openings 28 into the interior of the head. In other words, secondary air passes into the combustion head not only through the openings of the shutter 27, but also through the openings 28, the broadened rear edges of the vanes assisting in directing the air downwardly through the openings 28 which are in registration with the rear ends of the vanes.

The web 22 is also provided with openings 30 and 31 in which may be secured the tubular supports 32 and 33 for the electrodes 34 and 35, which latter, as shown in FIG. 1, are adjacent the discharge end of the nozzle 25 so as to ignite the spray issuing from the nozzle.

With the above construction it will be apparent that I have provided a combustion head of relatively simple construction which may be manufactured economically and which at the same time will provide for efficient combustion of the fuel. It will be noted that the vanes which give a whirling or turbulent motion to the combustion air are mounted on the cylindrical part 14- of the combustion head so that the combustion head may be inserted into the cap 11 and positioned therein by the vanes with the conical portion of the head cooperating with the conical interior surface of the cap 11 to prow'de a forwardly and inwardly directed passage to deliver the combustion air toward the axis of the head. Moreover, it will be seen that the secondary air will be deflected by the rear ends of the vanes so that it passes through the openings 28 to the interior of the head. This provides for effective combustion of the fuel, and the engagement of the vanes 16 with the inner surface of the cap 11 will locate the combustion head with respect to the cap and provide the necessary space between these two members, with the outer surface of the cone 15 being substantially parallel to the cone 13.

Moreover, the vacuum breaker openings 18 provided in the conical portion 15 of the combustion head prevent any tendency for the flame to be drawn back into the nozzle when the burner is shut off. The provision of the 'Web 22 in the drum 20 provides for support of the fuel tube 23 as well as the electrode holders 32 and 33 and for the support of the shutter 27.

In FIGS. 6 to 8 of the drawings I have shown a somewhat modified form of my invention. In this instance the burner comprises an outer casing 40 in the forward end of which is inserted a cap 41 having a cone-shaped forward end 42, the inner surface of which is substantially parallel with the cone-shaped outer surface 43 of the forward portion of the combustion head. This combustion head, as shown in FIGS. 6 and 7, also comprises the cylindrical portion 44 having helically directed vanes 45 to give a turbulent or whirling motion to the air in a manner similar to the vane 16 previously described.

Moreover, it will be seen that these vanes locate the combustion head within the cap 41 although the position of the head longitudinally of the cap to provide the proper space between the members 43 and 42 may be determined by the fuel tube 45 which is secured to the head as hereinafter described. The fuel tube may be secured against longitudinal movement in the casing 40 by the set screw 47 which is screwed into a thimble '48 on the rear end of the casing. With this arrangement the fuel tube may be adjusted to some extent forwardly and rearwardly but in general its position will be determined by contact of the forward ends of the vanes 45 with the inner tapered surface of the cone-shaped portion 42 of the cap 41. The portion 43 of the combustion head may be provided with vacuum breaker openings 49 as before.

Rearwardly of the cylindrical portion 44- of the combustion head is a drum member 50 which may be secured in place by screws 51 passing through the wall of the drum member into the rear edge of the portion 44. The rear end of the member 50 is closed except for openings provided for the tube 46 and for the electrode holders 52 and 53 and also for openings 54 to admit air to the interior of the combustion head from the casing '40. As many of the openings 54 may be provided as is desired, these openings in some degree taking the place of the shutter mechanism 27 shown in FIGS. 1 and 5.

Also the drum member 50 is provided with a plurality of openings 55 arranged at its front edge adjacent the rear edge of the portion 44. It will be noted that there will be one of these openings in registration with the rear edge of each of the vanes 45 and each of these vanes is provided with a rear end 56 of tear-drop shape as to cause the air to flow through the openings 55 into the interior of the combustion head. Additional openings 55 may be provided between the vanes as illustrated.

Combustion air may be furnished through a lateral opening 57 provided in the casing 40, but it will be noted that in this instance the rear end of the casing 40 is closed by the end plate 58 which supports the fuel tube 46.

It will be apparent that the combustion head shown in FIGS. 6 to 8 is quite similar to that shown in FIGS. 1 to 5 with the exception of the construction of the drum member 50. However, even in the case of this member there are similarities of construction between the two forms of the invention in that the openings 55 for the entrance of secondary air to the interior of the combustion head shown in FIGS. 6 to 8 are located at the rear ends of the vanes so that the air will be deflected to the interior of the combustion head in a manner similar to that described in connection with the form of my invention shown in FIGS. 1 to 5.

While I have shown and described some preferred embodiments of my invention, it will be understood that it is not to be limited to all of the details shown, but is capable of modification and variation within the spirit of the invention and within the scope of the claim.

What I claim is:

An oil burner comprising a housing, a hollow combustion head within the housing, a nozzle mounted within said head, said head comprising a cylindrical portion having helically directed vanes on its outer surface between rected portion of conical shape exteriorly, a hollow drum member rigidly secured to the rear end of the cylindrical portion of the head and having openings through its outer wall, at a point rearwardly of the nozzle, registering with and immediately adjacent to the rear edges of said vanes 5 whereby a part of the air passing through the housing is caused to flow through said openings into the head by said vanes, and said vanes being of tear-drop shape at their rear edges in front of said openings.

References Cited in the file of this patent UNITED STATES PATENTS 6 McClammy et a1 Sept. 10, 1940 Fisher Nov. 16, 1943 Neiman et a1. May 15, 1951 Pohle July 15, 1952 Winters Nov. 4, 1952 Hirtz Apr. 14, 1953 Dennis et a1 Apr. 27, 1954 OTHER REFERENCES Kooiker: Abstract of application, Serial No. 98,999, published September 11, 1951; 650 O. G. 599.

UNITED STATES PATENT, OFFICE CERTIFICATE OF CORRECTION Patent. No, 3,007,515 November 7,, 1961 I I John M; Furolock It is herebj certified that error a ent requiring correction and that the said Letters Patent should read as corrected below. I 4

Column 4, line 70 after "between" insert said surface and the housing, and a second forwardly di-= Signed and seal-ed'this 17th day of April 1962.

(SEAL) Attest:

ESTON G. JOHN-SON DAVID L. LADD Attesting Officer Commissioner of Patents 

